The U.S. finally clawed back all the jobs lost since the recession hit in late 2007, a watershed in a grindingly slow recovery that finds a labor market still in many ways weaker now than before the downturn.

U.S. payrolls in May hit an all-time high after the first four-month stretch of job creation above 200,000 since the boom days of the late 1990s, according to the Labor Department's latest employment report. In all, employers added 217,000 jobs last month, nudging payrolls above the prior peak in January 2008. The...